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Angle-resolved photoemission spectroscopy using a micro-focused beam spot (micro-ARPES) is becoming a powerful tool to elucidate key electronic states of exotic quantum materials. We have developed a versatile micro-ARPES system based on synchrotron radiation beam focused with a Kirkpatrick-Baez mirror optics. The mirrors are monolithically installed on a stage, which is driven with five-axes motion, and are vibrationally separated from the ARPES measurement system. Spatial mapping of the Auphotolithography pattern on Si signifies the beam spot size of 10 $\mu$m (horizontal) x 12 $\mu$m (vertical) at the sample position, which is well suited to resolve the fine structure in local electronic states. Utilization of the micro beam and the high precision sample motion system enables the accurate spatially resolved band-structure mapping, as demonstrated by the observation of a small band anomaly associated with tiny sample bending near the edge of a cleaved topological insulator single crystal., Comment: 21 pages, 8 figures

Beamline 13 of the Photon Factory has been in operation since 2010 as a vacuum ultraviolet and soft X-ray undulator beamline for X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), and angle-resolved photoelectron spectroscopy (ARPES) experiments. The beamline and the end-station at branch B have been recently upgraded, enabling microscopic XPS, XAS, and ARPES measurements to be performed. In 2015, a planar undulator insertion device was replaced with an APPLE-II (advanced planar polarized light emitter II) undulator. This replacement allows use of linear, circular, and elliptical polarized light between 48 and 2000 eV with photon intensities of 109–1013 photons s−1. For microscopic measurements, a toroidal post-mirror was renewed to have more focused beam with profile sizes of 78 µm (horizontal) × 15 µm (vertical) and 84 µm × 11 µm at photon energies of 100 and 400 eV, respectively. A high-precision sample manipulator composed of an XYZ translator, a rotary feedthrough, and a newly developed goniometer, which is essential for microscopic measurements, has been used to control a sample specimen in six degrees of freedom, i.e. translation in the X, Y, and Z directions and rotation in the polar, azimuthal, and tilt directions. To demonstrate the performance of the focused beams, one- and two-dimensional XPS and XAS scan measurements of a copper grid have been performed. It was indicated from analysis of XPS and XAS intensity maps that the actual spatial resolution can be determined by the beam size.

Many wave energy converters have been developed so far, but there are still many engineering problems to be applied to fishery buoys. Gyroscopic generators that use a rotating mass is characterized by the possibility of downsizing, but since low speed precession rotation is used to generate power, efficiency is so low that they do not work in the size of 1 m3. In this study, a new mechanism is proposed which consists of bevel gears, two clutches and gimbals to accelerate spin by transmitting precession torque mechanically to the spin shaft in order to realize high efficiency power generation by high speed spin rotation. Gear-driven gyroscopic generator using this mechanism which has higher efficiency and longer lifespan than former generators is expected to be applied to the power source of the small ocean monitoring buoys for efficient fisheries. A gyroscopic power generator using the accelerating mechanism with flywheel of diameter of 300 mm was designed, and the accelerating mechanism of the generator was manufactured. An experiment was conducted in which a rotating vibration of 0.5 Hz was applied to confirm the effectivity of the mechanism. The spin speed increased from 35.6 rpm to 225 rpm due to the precession torque. Designed generator is expected to output power of 3 W from this result.

At a soft X-ray beamline with an undulator source, significant heat generation at the first-mirror chamber and light emission at the viewport were found, which can be explained by photoelectrons from the mirror. The chamber temperature increases up to approximately 50°C over a period of several hours. A photoelectron shield consisting of thin copper plates not only prevents the heat generation and light emission but also improves the pressure of the vacuum chamber, if a voltage of a few tens of V is applied to the shield. The total electron yield of the shield reached as much as 58 mA under high heat-load conditions, indicating the emission of numerous photoelectrons from the first mirror. Heat-balance analyses suggest that approximately 30% or more of the heat load on the first mirror is transferred to the surroundings.

To realize a small-sized floating-type wave energy converter, a vibrational power generator that uses the gyroscopic effect and a geared acceleration mechanism is presented. First, equations of motion for the spin acceleration mechanism are derived. Next, numerical analyses are presented to show that the spin velocity of the gyro-flywheel is accelerated or decelerated by the rotating vibration, and the convergent power generations at various vibration frequencies are calculated. In addition, a simple equation that expresses the relationship between the vibration and equipment parameters and the convergent power generation is derived. The result shows that the generated power is 10 W when the flywheel diameter is 600 mm, the weight is 20 kg, the input frequency is 0.2 Hz, and the amplitude is 10°. Finally, an experimental apparatus with a spin acceleration mechanism containing a flywheel 300 mm in diameter is fabricated to show that the experimental and calculated steady-state spin and precession velocities agree when the vibration period is 1.5 and 2.0 s.

In order to realize a small-sized energy harvester with high output, this study prototypes a small motor-driven gyroscopic power generator. Supplying energy to sensors and devices is the biggest problem for Internet of Things (IoT) systems. One solution is gyroscopic power generators, which are a type of vibrational generator that amplify the inertia force of weights by rotating them at high speed, and in doing so can obtain greater output than conventional generators that use simple vibration for the same mass weight. This paper reports on a motor-driven type gyroscopic generator in which the flywheel is spun with an embedded motor, and which is superior in applicability to random vibration generators. The generators of this type that have been studied thus far are very large and have been primarily used for wave power generation in the ocean. However, when the shape of this gyroscopic power generator type is miniaturized proportionally, the output per volume decreases in proportion to the fifth power of the dimension. This makes it difficult to maintain the power output while miniaturizing the generator size. In this research, the structure of the gyroscopic power generator is thoroughly refined and miniaturization is realized by making full use of the available space. By using a motor with high design freedom, the spindle motor and flywheel are unified. From this accomplishment, not only is the required space reduced, the number of mechanical parts and the friction loss are decreased as well. The prototype generator has a size of about 150 mm on its long side. When a swinging vibration of 50 degrees in amplitude and 2 Hz in frequency is applied, a net output of 0.104 W is obtained. This output power is sufficient to drive sensors and low power wide area (LPWA) radio circuits.

The present status of a new vacuum ultraviolet/soft X-ray (VUV/SX) beamline (BL-13A) used for the study of organic thin films adsorbed on surfaces is described. The base pressure of BL-13A is maintained below 1×10−8 Pa in order to prevent contamination of the optics by residual gases. The measured performance is as follows: photon-energy region, 30-1,200 eV; photon flux, 109-1011 photons s−1; photon-energy resolution (E/ΔE), 10,000 at a photon energy of 401 eV; spot size (horizontal\ imes;vertical) at the second focus, ≈630×120 μm; photon-energy drift, ≤±0.02 eV at a photon energy of 244.39 eV; reduction of photon flux in the C K-edge region, ∼50%.

One-body type water- and air-cooling fixed masks made of forged 0.2% beryllium copper alloy have been developed, and successfully applied for the front end of a new undulator beamline, BL-13A, at the Photon Factory in Tsukuba, Japan. Advantages of the masks are a simple structure, no welding, low cost, high duration, and an extremely low out-gassing rate. Forged 0.2% beryllium copper alloy is demonstrated to be a valuable material for synchrotron radiation instruments.

Carbon contamination of a chromium-coated mirror was removed by exposure to oxygen activated with non-monochromated synchrotron radiation. Higher-order harmonics of the chromium-coated mirror are much smaller than those of a gold-coated mirror in the carbon K-edge region., Carbon-free chromium-coated optics are ideal in the carbon K-edge region (280–330 eV) because the reflectivity of first-order light is larger than that of gold-coated optics while the second-order harmonics (560–660 eV) are significantly suppressed by chromium L-edge and oxygen K-edge absorption. Here, chromium-, gold- and nickel-coated mirrors have been adopted in the vacuum ultraviolet and soft X-ray branch beamline BL-13B at the Photon Factory in Tsukuba, Japan. Carbon contamination on the chromium-coated mirror was almost completely removed by exposure to oxygen at a pressure of 8 × 10−2 Pa for 1 h under irradiation of non-monochromated synchrotron radiation. The pressure in the chamber recovered to the order of 10−7 Pa within a few hours. The reflectivity of the chromium-coated mirror of the second-order harmonics in the carbon K-edge region (560–660 eV) was found to be a factor of 0.1–0.48 smaller than that of the gold-coated mirror.

The undulator beamline BL-2C was constructed for measurements of soft X-ray spectroscopy. It is equipped with a varied line-space plane grating monochromator. High energy-resolution, high photon-flux and tiny spot-size have contributed to research on electronic structure of gaseous samples, solid samples and surfaces. In order to carry out further sophisticated measurement, we have improved the beamline at the following three points. First, optical elements were re-aligned again with great care for higher energy-resolution. To demonstrate the energy-resolution, we measured absorption spectrum of oxygen 1 s σ → π * excitation and evaluated E/ Δ E to be more than 10,000. Secondly, mirror holders were altered to reduce the effect of heat load. The remodeling and the replacement of the optical-element holders resulted in energy-drift becoming negligible. Thirdly, the carbon-contaminated optical elements were cleaned by ozone-cleaning method. The photon flux at the carbon absorption-edge is recovered by the cleaning.

Carbon contamination of optics is a serious issue in all soft X-ray beamlines because it decreases the quality of experimental data, such as near-edge X-ray absorption fine structure, resonant photoemission and resonant soft X-ray emission spectra in the carbon K-edge region. Here an in situ method involving the use of oxygen activated by zeroth-order synchrotron radiation was used to clean the optics in a vacuum ultraviolet and soft X-ray undulator beamline, BL-13A at the Photon Factory in Tsukuba, Japan. The carbon contamination of the optics was removed by exposing them to oxygen at a pressure of 10(-1)-10(-4) Pa for 17-20 h and simultaneously irradiating them with zeroth-order synchrotron radiation. After the cleaning, the decrease in the photon intensity in the carbon K-edge region reduced to 2-5%. The base pressure of the beamline recovered to 10(-7)-10(-8) Pa in one day without baking. The beamline can be used without additional commissioning.

Recent advances in high‐throughput techniques for macromolecular crystallography have highlighted the importance of structure‐based drug design (SBDD), and the demand for synchrotron use by pharmaceutical researchers has increased. Thus, in collaboration with Astellas Pharma Inc., we have constructed a new high‐throughput macromolecular crystallography beamline, AR‐NE3A, which is dedicated to SBDD. At AR‐NE3A, a photon flux up to three times higher than those at existing high‐throughput beams at the Photon Factory, AR‐NW12A and BL‐5A, can be realized at the same sample positions. Installed in the experimental hutch are a high‐precision diffractometer, fast‐readout, high‐gain CCD detector, and sample exchange robot capable of handling more than two hundred cryo‐cooled samples stored in a Dewar. To facilitate high‐throughput data collection required for pharmaceutical research, fully automated data collection and processing systems have been developed. Thus, sample exchange, centering, data collection, and data processing are automatically carried out based on the user’s pre‐defined schedule. Although Astellas Pharma Inc. has a priority access to AR‐NE3A, the remaining beam time is allocated to general academic and other industrial users.

The design and commissioning of a new soft X‐ray beamline, BL‐16A, at the Photon Factory is presented. The beamline consists of a pre‐focusing mirror, an entrance slit, a variable‐included‐angle varied‐line‐spacing plane grating monochromator, and a post‐focusing system as usual, and provides circularly and linearly polarized soft X rays in the energy range 200–1500 eV with an APPLE‐II type undulator. The commissioning procedure for the beamline optics is described in detail, especially the check of the focal position for the zero‐th order and diffracted X rays.

A planar undulator beamline, BL‐13A, covering 30–1,000 eV has been constructed in the Photon Factory. The main scientific targets are investigations of organic thin films and biomolecules adsorbed on well‐defined surfaces using angle‐resolved photoelectron spectroscopy, X‐ray photoelectron spectroscopy, and X‐ray absorption spectroscopy. A variable‐included‐angle Monk‐Gillieson mounting monochromator with varied‐line‐spacing plane gratings is used to achieve a high photon flux of 1010–1012 photons/s with a high resolution (E/ΔE) of 7,000–30,000. A typical spot size on the sample position is estimated to be 130 μm (horizontal)×40 μm (vertical). After commissioning, BL‐13A will be open for users from January 2010.

The design and performance of a 24 m high-resolution spherical grating monochromator (H-SGM) for the undulator beamline (BL-16B) at the Photon Factory are described. With three interchangeable gratings of 400, 900 and 2000 lines mm−1, the H-SGM is designed to cover the photon energy range 40–600 eV. With a resolving power of approximately 2000 in the photon energy range 40–530 eV, more than 1011 photons s−1 have been measured. The best resolutions obtained so far, at a substantially lower photon flux, are greater than 10 000 at 250 eV and 8000 at 400 eV

Two types of simple non-evaporable getter (NEG) assemblies have been constructed using commercial St707 strips. The first one can be activated by direct current heating at 15 A. The second can be activated by indirect heating using a tantalum heater at 12 A. The base pressure of the chambers pumped solely by the first and the second NEG assemblies reached 2.4×10−8 and

A new grazing incidence soft x-ray monochromator has been commissioned on the undulator beamline BL-2 of the Photon Factory. The monochromator has been designed to meet the demands for high-resolution soft x-ray spectroscopy. The monochromator has employed a varied space plane grating and a configuration with sagittal focusing and converging beam to satisfy the requirement. According to analytical estimation and ray tracing simulation, the high resolving power beyond 10000 can be obtained over the full energy range from 250 to 1400 eV. Preliminary experiments have been done on three points concerning the resolving power, photon flux, and spot size. The results have showed the typical resolving power from 7500 to 10000, the absolute photon flux ofthe order of lOb photons/s/300mA/O.02%BW, and the spot size ofO.1(V) x 0.9(11) 2FW at the sample position.

The design and performance of a new soft X-ray beamline BL-11A at the Photon Factory (PF) are presented. A Hettrick-type grazing-incidence monochromator equipped with three varied-line-spacing plane gratings was designed and constructed at a bending-magnet source of the PF 2.5 GeV storage ring. An 800 lines mm−1 laminar grating produced by aspheric-wavefront holographic recording optics, as well as a mechanically ruled blazed one, were tested. A resolving power of more than 4500 was achieved at 400 eV with either grating, and ∼1010 photons s−1 are available at a resolving power of 2000. High photon flux enables low-concentration samples, such as surface adsorbates, to be studied. A simple scanning mechanism for a wide energy range is quite useful for EXAFS measurements on light elements such as C, N and O.

We report on the present status of a vacuum ultraviolet and soft X-ray undulator beamline, BL-13A, located at the Photon Factory. BL-13A is mainly dedicated to the study of organic thin films adsorbed on well-defined surfaces, using angle-resolved photoelectron spectroscopy (ARPES), X-ray photoelectron spectroscopy (XPS), and X-ray absorption spectroscopy (XAS). The photon-energy resolution (E/ΔE) is estimated to be about 10000 at a photon energy of 64 eV with an exit-slit width of 30 μm. The photon intensity is estimated to be 2.9 × 1012 to 5.6 × 108 photons/s for photon energies of 30-1600 eV with an exit-slit width of 100 μm at the ring current of 450 mA. An ultrahigh vacuum (UHV) chamber equipped with an electron-energy analyzer (Gamma Data/Scienta, SES 200) is used as the main end station for ARPES, XPS, and XAS measurements. A sample can be transferred from a UHV chamber for sample preparation or from a UHV chamber for the evaporation of organic materials. The sample-holder acceptors are equipped with a heating and cooling system. The overall electron-energy resolution is estimated to be about 12 meV at a photon energy of 30 eV.

Progress in performance of a beamline for a 60‐period soft x‐ray undulator of the 2.5‐GeV Photon Factory storage ring was made by implementation of low emittance operation of the storage ring and improvements of beamline and monochromator units. Monochromated photon flux of up to 1012 photons/s has now been achieved at maximum in ordinary operating conditions of the ring current of ≊200 mA with resolution of 500–1000 over the soft x‐ray region from 410 eV to a few keV of photon energy.